Ink refill tank



FIG. 1 is a perspective view of an ink refill tank showing our new design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a front elevational view thereof;

FIG. 6 is a rear elevational view thereof; and,

FIG. 7 is a right side elevational view thereof.

The broken lines are for purposes of illustration only and form no part of the claimed design. 

The ornamental design for an ink refill tank, as shown and described. 